I love C. S. Lewis' Til We have Faces!
If you want someone modern you may like some of Frank E. Peretti's work-- Monster is good, and I also loved his Darkness series. The Oath is pretty graphic.
You may like Ted Dekker, he is considered controversial.
I also love Francine Rivers, one of her books-- The Last Sin Eater, was made into a movie. I never saw the movie, but loved the book.